Summary

A new study shows that much land can no longer absorb or break down the increasing amounts of fixed nitrogen--compounds such as ammonia and nitrogen oxides--so growing quantities end up in waterways, touching off coastal algal blooms, including the notorious red and brown tides, and impairing fisheries. Other work has detailed the toll the excess nitrogen is taking on land plants, as it displaces valuable nutrients from forest soils. If unchecked, entire ecosystems ranging from forests to coastal waters could be overwhelmed.